Ship protection



H. .l. W. FAY.

SHIP PROTECTION.-

APPLICATION FILED AUG-26' l9l8.

, 1,416,950, Patented May 23,- 1922.

4 SHEETSSHEET 1.

H. J. W. FAY.

SHIP PROTECTION. APPLICATION FILED AuG.26, 1918.

4 SHEETS-SHEET 2.

Patented May 23, 1922.

H. J. w. FAY. SHIP PROTECTION. APPLICATION FILED AUGJZG, EH8.

Patent ed May 23, 1922.

4 SHEETS-SHEET 3.

\/r' 70R: 2 mfl fia I 50 9 7- Take A H. J. W. FAY.

SHIP PROTECTION.

APPLICATION FILED maze. ms.

Patented May 23, 1922.

4 SHEETS-SHEET 4.

HAROLD J. w. FAY, or w'ns'rsono, massacrrnsnrrs. AssIeNoa r0 sUBMARI'NE SIGNAL COMPANY, or ron'rLaNn. .uiarNn, A ooaronArroN on MAINE.

SHIP PROTECTION.

Application filed August 26, 1918.

To all whom it may concern.-

Be it known that I, HAROLD J. V. FAY, of \Vestboro, in the county of Worcester and State of Massachusetts, a citizen of the United States, have invented a new and use ful Improvement in Ship Protection, of

which the following is a specification.

Experience has shown that ships when mechanically propelled, and especially submarines when running submerged, propagate sounds through the water which in the form of compressional waves manifest their pres ence to other vessels, which may otherwise be unaware of their presence. By means of a small submerged microphone I have observed sounds from such vessels from a distance of approximately two miles.

The source of such sounds I believe to be mechanical vibrations due to the engines, etc., on board the ship, which vibrations are transmitted through the sides of the hull, the propeller shafts and blades, etc., such vibrating metal being peculiarly adapted to radiate sound waves in water. This is especially true of a submarine the hull of which is susceptible of considerable vibration. Usually its propelling machinery is concentrated in its after part so that the vibrations emanating from the entire hull emanate with greater and considerable force from a comparatively small area near the stern.

It is well known that if sound waves meet in the path media of different densities their force is definitely diminished, if not entirely dissipated, especially when one or more of these media are elastic so that portion of the energy of the waves is taken up by such elasticity. Such waves comprise a compressional part and an extensional part, the applicant provides means about the ships hull or such a portion thereof as gives out the strongest vibrations, whereby the energy of such vibrations is spent in compressing an elastic medium or elastic media instead of acting directly on the water. Thus their radius of effectiveness in giving warning of an approaching ship is materially reduce'd and, so far as audibility is concerned, the ship may approach quite near to an enemy ship without being noticed.

My invention consists therefore 1n pr0- viding a submarine or other vessel with a sound-absorbing protector of such character Specification of Letters Batent.

Patented May 23,1922.

Serial No. 251,417.

that vibrations originating in the vessel will be absorbed or nullified to a greater or less degree and hence will not give notice of the location and movements of the vessel while it is at a material distance from the observer or enemy ship. It is known that air bubbles, inflated rubber tubes, etc., will act as sound absorbers, and I do not mean to limit myself to any specific form of sound absorbing means in carrying out my inven tion.

My invention will be understood by reference to the drawings in which it is illustrated diagrammatically as applied in various forms to various kinds of vessels.

Figure 1 is a side elevation of a submarine to which my invention is applied.

Fig. 2 is a cross section, and Fig. 3 is a plan of the stern thereof, showing especially the diving rudder.

Fig.4 is a side elevation, and Fig. 5 is a plan of the stern of a submarine showing another form of device for absorbing the noises from the propeller and rudder.

Fig. 6 being a section on line 6-6 of Fig. 5.

Fig. 7 is a side elevation of a submarine showing another embodiment of my invention, Figs. 8 and9 being sections on lines 88 and 9-9 of Fig. 7

Fig. 10 is a side elevation showing the application of my invention to a sailing vessel having an auxiliary engine, which may be used or not. as desired, and

Fig. 11 is an enlarged plan of the stern thereof.

In the forms of my invention shown air is utilized either directly or indirectly as the medium by which the vibrations of the vessel are nullified.

Referring first to the application of my invention shown in Fig. 1, A is a submarine, the hull or skin of which is perforated as at a, each perforation being connected by ,a suitable coupling 6 with a pipe B, which nearly encircles the interior of the hull and is capped or closed at each end. A coupling 0 connects each pipe B with a pipe C running to an air compressor or compressed air reservoir C conveniently located within the hull. A series of lines of tubes D, preferably of flexible and compressible material such for example as rubber, run lengthwise outside the hull and are attached thereto by bands D running round the hull or other wise.

Each opening r4 is connected withoue of the tubes D so that air from the air reservoir (i 'tills the tubes D. Vibrations inside the vessel and the vibrations of the vessels skin will be largely expended in compressing the tubes and the air within them rather than in setting up compressional waves in the water. Their force is thus reduced so that they will become ineffective, certainly within a reasonable distance of the vessel.

in addition, as shownin Figs. 1 and 3, the rudder E and the diving rudder F are provided with similar tubes 6 and f, respectively, which are also suitably connected with the air pump or reservoir so that they may become part of the same system or otherwise supplied with compressed air, and the vibrations from them are thus also absorbed. The noise-absorbing system may be otherwise arranged or especially arranged accordin to the location in the hull of the main source of vibrational or other noises, and the arrangement, number and size of the tubes may be varied to suit any particular situation.

In Figs. 4, 5 and 6 are shown other similar means especially "for absorbing or nullifying the propeller and other vibrational noises which orginate at the stern of the ship and is not used in addition to a hull-protecting system. In this case a pipe B at the stern connected with the air pump or reservoir by the pipe C through a coupling 0. is provided with four or more couplings 72 with each of which is connected a tube D long enough preferably'to extend to the rear of the propellers and rudder and also preferably open at the outer end. These tubes D are of such character as not to interfere with the mechanism originating the noise which they are to absorb. Their outer ends being open, they blow air out into the water which bubbles up round the stern and of itself acts as a medium upon which the energy of the vibrations may expend itself.

Figs. '7, 8 and 9 show the hull of vessel from' which the tubes outside the vessel have been omitted and rigid tubes G are riveted to the inner skin so that they serve both as braces and as air passages B They are connected with the source of compressed air and are provided with openings at through which the air passes out into the open water to form the compressible medium to absorb the energy of the compressional. waves set up within the vessel. In this case the air is blown out under considerable pressure and bubbling up around the hull acts as a medium through which the compressional waves must pass from the vessel and which, because it becomes mixed with the water in proximity with the hull, serves, with the water as a container, to absorb compressional vibrations originating in the vessel. l hc sound waves leaving the hull. pass into this elastic medium and are reduced in strength and become ineffective as a. warning to hostile vessels outside a limited radius.

This construction with sufiicicnt air pressure behind it will surround the submerged. hull of the vessel with bubblings of air which will to a large extent absorb the energy of the vibrations of the hull and its contents and. the radiations from the hull of the vibrations originating therein.

InFigs. 10 and 11 I have shown the application of this same invention to what is ordinarily called. an auxiliary that is to say, a sailing vessel having an engine propeller which can be used in the case of calm weather or under any other desirable circumstances, In this case the hull is lettered H and from its stern project, as usual in such cases, a propeller 71 and rudder 7L1. In this case the air supply is brought by the pipe j from an air compressor (not shown) to swinging yoke J, which is perforated as at 7' The pipe 7' is connected to the pipe J by a coupling J of a character well known and such that the pipe J may be swung in it; and at J is a similar device, which, however, is not a coupling but a capped or otherwise closed end for the pipe J in which its end may likewise swing. 11 other words, the pipe J is capable of being lowered. to a. position such as is shown in Fig. 10 where it is held by achain y"", or it may be raised by suitable means to the position shown in dotted lines in Fig. 10. When in its lowered position it sends out under water its cloud of bubbles which absorb more or less the compressional waves sent out from the stern of the vessel. Then the propeller, however, is not in operation, the pipe may be raised so not to interfere with the speed of the vessel, for in its lowerred position it lies considerably below the water level.

Other embodiments of my invention will occur to those skilled in the art, its point being that if compartments having walls capable of yielding to pressure and filled with an elastic medium (and a mass of air bubbles in the water may for this purpose be considered a mass of compartments having elastic walls and filled with an elastic medium) are placed in reasonably close proximity to the masses of metal which are acting as sound producers and radiator under water, there is a marked absorption 0 a very considerable proportion of the energy so originating.

The air containers should preferably be below the water line or so located as to receive and absorb the compressional waves due to the vibrations originating in or about the vessel, whichever form of container is used, whether the hose form or the form in which the container is the water itself, i. e., the bubbles which are formed by the blowing out of air from the tubes inside the vessel. For in either case there is an elastic medium located between the source of vibration and the outside medium, viz: the water on which, were it not for this screen, the energy of the vibrations would act to convey intelligence to the distant observer, and thus utilize such energy.

lVhen the form of my invention shown in Figs. 1 and 2 is used, as the compressional waves radiate from all points in the hull,

the tubes should be quite near together so that these waves which originate between the tubes in radiating from their points of origin in the skin or" the hull, will to a large extent be interrupted by the tubes themselves and only those normal to their points of origin will strike out between the tubes. The size and distance apart of the tubes will depend upon the circumstances of each particular case.

In the form of my invention shown in Figs. 7, 8 and 9 a more complete shield of energy absorption will be provided.

Figs. 10 and 11 show a way in which the shield is arranged to be used when and where it will be most needed. This will not necessarily be at the stern.

So far as "I am aware this solution of the problem of how to deaden the sounds 0rig inating on a vessel, either because of the vibration of its machinery or of its hull, in passing through the water or otherwise so that its location will not be betrayed to a distant observer, is broadly new with me, and I do not mean to limit myself to the precise means shown for accomplishing the desired result.

\Vhat I claim as my invention is l. Mechanism of the kind described comprising a vessel. 4 source of compressed air located thereon, and means whereby such compressed air may be delivered at points about said vessel to serve as an absorbent to compressional waves originating in said vessel, said in ans comprising a series of elastic tubes located at different levels about the vessels sides and connections between said tubes and said compressed air source.

2. Mechanism of the kind described comprising a vessel, a vibratory means located on said vessel and a source of compressed air located thereon, and means whereby such compressed air may be delivered at points about said vessel to serve as an absorbent to compressional waves originating in said *essel, said means comprising a series of elastic tubes located at different levels about the vessels sides and connections between said tubes and said compressed air service.

8. lVlechanism of the kind described comprising a vessel, a vibratory means located on said vessel and a source of compressed air located thereon, and means whereby such compressed air may be delivered at points about said vessel to serve as an absorbent to compressional waves originating in said vessel, said means comprising a series of tubes and connections between said tubes and said compressed air source, said tubes being located upon the outside of the vessel to receive compressional waves originating at said vibratory means.

HAROLD J. W. FAY. 

